The Rolls MX124 Pro-MixIV mixes 4 microphones into two transformer balanced outputs. It has four XLR inputs, each with individually switchable phantom power, and Low Cut switches (100 Hz high pass filter), a Level control, and a Pan control. As mentioned, it has two transformer balanced, XLR outputs. A 1/4 inch Aux/Headphone output has been provided along with a Clip indicator, Power indicator, and Power switch. The unit is also powered by two 9-Volt alkaline batteries or the included 15VDC power supply.